Regarding Graphic of the day

[Jpflex]

Why is there no double pole main breaker on this panel terminating onto phase A and B feeders on top or line side of the panel according to:

408.36 switchboards, switchgear, and panel boards. Overcurrent protection. In addition to the requirements of 408.30 a panel board shall be protected by an overcurrent protective device having a rating not greater than that of the panel board. This overcurrent protective device shall be located within or at any point on the supply side of the panel board.


The branch circuit breakers do not qualify for this rule correct? Or is there possibly a breaker upstream separate from this panel?

I’ve seen panels being sold like this without such a main breaker to protect the load center

 

[Little Bill]

We don't details but that is a MLO panel. It's most likely fed from another source. Or it might be using the "six throws of the hand" exception for MLO panels.
But in truth, it's just a drawing and the subject was just about a circuit breaker.

 

[Jpflex]

What is an MLO panel?

 

[LarryFine]

What is an MLO panel?

Main Lug Only, as opposed to Main Breaker.

 

[Jpflex]

Main Lug Only, as opposed to Main Breaker.

But regardless if a distribution panel, MLO or main panel all will require OCPD on the supply side of breaker cabinet/ panel. I assume they have a separate disconnect breaker box upstream to this cabinet then

 

[roger]

But regardless if a distribution panel, MLO or main panel all will require OCPD on the supply side of breaker cabinet/ panel. I assume they have a separate disconnect breaker box upstream to this cabinet then

Notice the neutrals and EGC's are separated and there is no sign of a MBJ, this would be indicative of a downstream panel from the service disconnect.

 

[Little Bill]

But regardless if a distribution panel, MLO or main panel all will require OCPD on the supply side of breaker cabinet/ panel. I assume they have a separate disconnect breaker box upstream to this cabinet then

If it was a main breaker, read what the rule you posted says.

408.36 switchboards, switchgear, and panel boards. Overcurrent protection. In addition to the requirements of 408.30 a panel board shall be protected by an overcurrent protective device having a rating not greater than that of the panel board. This overcurrent protective device shall be located within or at any point on the supply side of the panel board.

As I said, it either has upstream protection or is using the "six throw" rule.

 

[Strathead]

But regardless if a distribution panel, MLO or main panel all will require OCPD on the supply side of breaker cabinet/ panel. I assume they have a separate disconnect breaker box upstream to this cabinet then

It doesn't have to have a separate disconnect. In most commercial cases, the upstream breaker is located in the distribution panel ahead of the MLO panel in a building with multiple panels. In smaller situations, you have to have a disconnect outside or nearest the point of entrance, so that will be your overcurrent protection. No need to spend the extra money on a redundant breaker in the panel.